The LEADLESS study's long-term follow-up has evaluated 32 patients with a slowed heartbeat, bradycardia, who successfully received St. Jude Medical's Nanostim™ leadless pacemaker at two hospitals in Prague and one in Amsterdam. The findings, which assessed device performance and patient outcomes through 12-months of follow-up, show pacing thresholds (0.43 volts) and sensing (10.32 mV) of the leadless pacemaker device are equivalent to those in traditional pacemakers. In addition, there was no experience of infections or failure to sense, pace, or communicate with the pacemaker.

"This is the first time we've seen one-year follow-up data for this innovative, wireless cardiac pacing technology and our results show the leadless pacemaker is comparable to traditional pacemakers, says Dr. Vivek Reddy, Director of Arrhythmia Services at The Mount Sinai Hospital who is the study's co-investigator and Chairman of its Steering Committee. "Our latest findings further support the promising performance and safety of this minimally-invasive, non-surgical pacing device. More long-term follow-up of these LEADLESS study patients will further our understanding of the potential advantages, benefits, and complication risks of leadless pacemaker technology, along with additional ongoing, larger trials.

In February, Dr. Reddy was the first to implant the leadless pacemaker in the United States at The Mount Sinai Hospital launching the multicenter clinical trial LEADLESS II which aims to further test the leadless pacemaker more widely for safety and efficacy in 670 patients at 50 centers across the US and Canada.

The miniature-sized, leadless cardiac pacemaker is placed directly inside a patient's heart without surgery during a catheter-guided procedure through the groin via the femoral vein. The device, resembling a tiny, metal silver tube and smaller than a triple-A battery, is only a few centimeters in length, making it less than ten percent the size of a traditional pacemaker. It works by closely monitoring the heart's electrical rhythms and if the heart beat is too slow it provides electrical stimulation therapy to regulate it. More than 4 million patients globally have a pacemaker, and 700,000 new patients receive one each year.

In comparison to a conventional pacemaker, the new-age leadless pacemaker eliminates the need for a surgical pocket and no visible pacemaker device under a patient's chest skin, no incision scar on the chest, no connector wires or leads, and no restrictions on a patient's daily activities. The device's benefits may also allow for less patient discomfort, infections, and device complications and dysfunction.

The LEADLESS study was funded by St. Jude Medical, the manufacturer of the Nanostim pacemaker.

Dr. Reddy receives financial compensation as a consultant and advisory board member for St. Jude Medical, the study sponsor and manufacturer of the Nanostim pacemaker system being evaluated in this study. In addition, in 2013 he received one-time financial compensation from St. Jude Medical in the form of an option buyout relating to St. Jude Medical's acquisition of Nanostim.

About the Mount Sinai Health SystemThe Mount Sinai Health System is an integrated health system committed to providing distinguished care, conducting transformative research, and advancing biomedical education. Structured around seven member hospital campuses and a single medical school, the Health System has an extensive ambulatory network and a range of inpatient and outpatient services—from community‐based facilities to tertiary and quaternary care.

The System includes approximately 6,600 primary and specialty care physicians, 12‐minority‐owned free‐standing ambulatory surgery centers, over 45 ambulatory practices throughout the five boroughs of New York City, Westchester, and Long Island, as well as 31 affiliated community health centers. Physicians are affiliated with the Icahn School of Medicine at Mount Sinai, which is ranked among the top 20 medical schools both in National Institutes of Health funding and by U.S. News & World Report.